Dual shielded syringe

Abstract

A dual shield mechanism provides passive protection of a syringe cannula. The automatic shield system may be used with a re-fillable syringe, and may be adapted for filling the syringe from a vial using a novel vial adapter without triggering the passive shielding mechanism.

What is claimed is: 
     
       1. A dual shielded re-fillable syringe with vial adapter, comprising:
 a tubular syringe body having a distal end, a proximal end, and features on the distal end adapted to engage a shield assembly, the shield assembly comprising:
 a hub having features on a proximal end thereof for engaging the distal end of the syringe body; 
 a needle fixed to the hub having a distal end extending from the hub and a proximal end in the interior of the hub which does not extend from the hub; 
 an inner shield having a tubular body at least partially encircling the needle; 
 an outer shield having a tubular body radially outward of the inner shield covering the needle in an initial position prior to injection and having an opening on the distal end thereof which receives the distal end of the inner shield; 
 a spring disposed to urge the inner shield distally through the opening in the outer shield towards the distal end of the needle; 
 an outer sleeve at least partially encircling the inner and outer shields; and 
 a releasable retaining feature retaining the inner shield in an initial position, wherein a predetermined proximal movement of the outer shield relative to the hub and into the outer sleeve during an injection releases the inner shield to urge the inner shield under the bias of the spring to a position covering the distal end of the needle; and a vial adapter, having: 
 
 a distal annular opening adapted to fit around the neck of a vial and a proximal annular opening extending opposite the distal annular opening from a transverse wall; 
 the transverse wall supporting a filler needle extending distally from the transverse wall adapted for insertion into a vial septum, and having a proximal end with an opening onto the proximal side of the transverse wall; 
 a medicament compartment having a side wall surrounding the opening on the proximal end of the filler needle and a septum forming a proximal end wall of the medicament compartment, said septum receiving the needle of the shield assembly; and wherein 
 the proximal annular opening engages the outer sleeve of the shield assembly so that when the vial adapter is engaged to the shield assembly, the medicament compartment is positioned in the opening on the distal end of the outer shield, the needle pierces the septum of the medicament compartment, and movement of the outer shield in a proximal direction relative to the hub is prevented. 
 
     
     
       2. The dual shielded syringe according to  claim 1 , wherein the syringe body and the hub are connected by a luer-style tapered connection. 
     
     
       3. The dual shielded syringe according to  claim 1 , wherein the syringe body is integrally molded with the hub. 
     
     
       4. The dual shielded syringe according to  claim 1 , wherein the shield assembly is snap fit into a distal opening on the syringe barrel. 
     
     
       5. The dual shielded syringe according to  claim 1 , wherein the releasable retaining feature comprises a tapered surface on the outer shield engaging a corresponding tapered surface on the inner shield causing rotation of the outer shield relative to the inner shield when the outer shield is moved proximally, which rotation causes the inner shield to be released from the initial position. 
     
     
       6. The dual shield syringe according to  claim 5 , wherein the outer shield is constrained to move axially, without rotation, for a predetermined amount of proximal movement of the outer shield prior to said rotation of the outer shield being initiated. 
     
     
       7. The dual shielded syringe according to  claim 6 , wherein the inner shield engages the hub to prevent rotation of the inner shield when the outer shield is caused to rotate.